fix: sqlite errors in removeOldRosterEntries on connecting
fix: updating contact status on service connection to show correct buddy availability
Revert "MUC notification: show nickname"

This reverts commit c4199202dbefc73b1db50b99957d02fb53dd81bd.

The notification code is broken, as it forwards the nickname to the
ChatWindow, which uses that as a title. Ouch.
MUC: sort participant list alphabetically